24 July 2021 Inconel®
Inconel 718 Alloy Steel Bar
INCONEL® alloy 718 (UNS N07718/W.Nr. 2.4668) is a high-strength, corrosion-resistant nickel chromium material used at -423° to 1300°F. The age-hardenable alloy can be readily fabricated, even into complex parts. Its welding characteristics, especially its resistance to postweld cracking, are outstanding.
The ease and economy with which INCONEL alloy 718 can be fabricated, combined with good tensile, fatigue, creep, and rupture strength, have resulted in its use in a wide range of applications. Examples of these are components for liquid fueled rockets, rings, casings and various formed sheet metal parts for aircraft and land-based gas turbine engines, and cryogenic tankage. It is also used for fasteners and instrumentation parts.
Chemical Composition of Inconel 718:
Element | |
|---|---|
| Carbon | |
| Manganese | |
| Phosphorus | |
| Sulfur | |
| Silicon | |
| Chromium | |
| Nickel | |
| Molybdenum | |
| Columbium | |
| Titanium | |
| Aluminum | |
| Cobalt | |
| Boron | |
| Copper | |
| Tantalum | |
| Iron |
Resistance to Corrosion and Oxidation of Inconel 718
Inconel 718 has good resistance to oxidation and corrosion at temperatures in the alloy’s useful strength range in atmospheres encountered in jet engines and gas turbine operations.
Physical Properties of Inconel 718:
Typical physical properties of Inconel 718 are summarized in the table below.
| Density | ||
|---|---|---|
| Specific Gravity | ||
| Melting Range |
Thermal Conductivity of Inconel 718:
The thermal conductivity at various temperatures for Inconel 718 are given in the following table.
Mechanical Properties:
The room temperature strength of the Inconel 718 alloy is substantially increased by precipitation heat treatment as the following data indicate. These values are properties specified for sheet, strip and plate in AMS 5596 and AMS 5597.
| Shape | Min (0.2% offset) | Min | (% in 2") |
|---|---|---|---|
Solution trated plus precipitation heat treated:
Min (0.2% offset) | Min | (% in 2") |
|---|---|---|
Typical short time tensile properties of Inconel 718 as a function of temperature are shown here for material solution treated and aged as follows:
- Solution Treatment: 1800°F (982°C) 1 hour
- Precipitation Treatment: 1325°F (718°C) 8 hours, Furnace Cool at 100°F (55°C) per hour to 1150°F (621°C) 8 hours